This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a continuing proposal for the Liddington laboratory, describing our overall program in structural biology at the SSRL. The major focuses are anthrax toxin and virulence factors from other high priority pathogens and emerging diseases, and their interactions with host factors, as well as host proteins involved in cell migration and inflammation. The work involves ab initio structure determination by MAD phasing, studies of protein-inhibitor complexes for rational drug design, and complexes with neutralizing antibodies for designing immune therapeutics. I report highlights of our studies for the 2005-2008 period in the context of our earlier work at SSRL, as well as our ongoing and future studies. This work illustrates how the SSRL has played a central and critical role in most aspects of our science ? using its tunability for primary structure determination/phasing;and/or the high brightness, collimation and stability of the SSRL source for the collection of high resolution data from demanding crystals. And all of this made possible and much more pleasant through the dedication of the outstanding User Support Group.